1. Field of the Invention
The present invention relates to a disc recording method and a disc recording apparatus whereby audio data is recorded and reproduced. More particularly, the invention relates to a method and an apparatus for recording data on the disc, the apparatus having a memory in which to store temporarily the data preparatory to recording onto the disc.
2. Background of the Invention
In general, audio signal recording apparatuses such as tape recorders do not start their actual recording operation at exactly the time when they are given a recording start instruction, illustratively by operation of a recording button. This is because it takes time for the mechanisms of the recording apparatus to start up or for them to switch from another mode to recording mode. That is, the recording of data onto a storage medium actually begins after the delay of a certain period of time. In other words, no audio signal can be recorded during that delay time onto the storage medium, with the result that the initial part of a conversation or other sound sequence to be recorded fails to register on the storage medium.
Take, for example, the tape recorder for conference recording purposes disclosed in Japanese Patent Laid-Open No. SHO/60-195753 (1985). This tape recorder is designed to be inactive while detecting no sound and to act only when recording the sound it detects. This kind of tape recorder is incapable of recording an initial part of a sound sequence due to the time of delay from detection of the sound sequence until the actual start of the mechanisms for recording.
One solution to the above deficiency is proposed in the form of a recording apparatus disclosed in Japanese Patent Laid-Open No. SHO/58-41453 (1983). This recording apparatus comprises an FIFO memory with a recording capacity large enough to accommodate that initial part of a sound sequence which corresponds to a predetermined start-up time of the apparatus mechanisms. That is, the FIFO memory stores audio data equivalent to the start-up time, the audio data being handled through the memory as part of the actual data to be recorded.
One disadvantage of the above recording apparatus is the inclusion of the FIFO memory that is provided specifically to prevent omission of the initial part of the sound sequence. The memory is expensive and requires space in the apparatus which in turn needs to be bulkier than other models.
When listeners of a radio broadcast want to record a program from the radio, they generally operate the recording button of the recording apparatus while listening to the program broadcast. In such cases, it often happens that the listeners realize that a particular program or a portion of it they have just heard should have been recorded. By the time they realize what they have missed, the program has already been broadcast and is generally irretrievable. If it is desired to record that chronologically preceding part of broadcast upon subsequent recognition thereof, the recording apparatus needs to be equipped with a FIFO memory of a relatively large capacity to store a certain stream of broadcast. However, the above-mentioned conventional recording apparatus fails to foresee such eventualities and has a FIFO memory only large enough to allow for the time of mechanical delay from execution of a recording start instruction until the actual start of the recording operation. Whereas radio listeners have the above-mentioned need to record desired programs intact from the beginning, the conventional recording apparatus fails to meet the requirement despite its FIFO memory.
Furthermore, installing a large capacity memory, which is expensive and bulky, is not a practical solution to the problem.